The deformation behavior of Al during equal channel angular pressing was calculated on the basis of a dislocation density-based model. The behavior of the material under equal channel angular pressing, including the dislocation density and cell size evolution as well as texture development, was simulated using the finite element method. The simulated stress, strain and cell size were compared with experimental data which were obtained by equal channel angular pressing for several passes in a modified Route-C regime. Good agreement between simulation results and experimental data, including strain distribution, dislocation density and cell size evolution, strain hardening and texture development was obtained. The stress was found to increase rapidly in the first equal channel angular pressing pass, the strain-hardening rate then decreased from the second pass onward. Calculations showed a non-uniform strain distribution evolving during equal channel angular pressing. The simulated cell size was also in good agreement with experiment, particularly with the observed rapid decrease of the cell size during the first pass, slowing down from the second pass onwards. Larger cells were found to form in the upper and the lower parts of the workpiece, where the strain was smaller than that in the middle part. Due to the accumulation of strain throughout the workpiece and an overall trend towards saturation of the cell size, a decrease of the difference in cell size with the number of passes was predicted.

Dislocation Density-Based Modeling of Deformation Behavior of Aluminium Under Equal Channel Angular Pressing. S.C.Baik, Y.Estrin, H.S.Kim, R.J.Hellmig: Materials Science and Engineering A, 2003, 351[1-2], 86-97